System of selective control



Se t. 9 1924. 1,508,359

E R. CARICHOFF SYSTEM OF. SELECTIVE CONTROL Filed Jan. 4, 1922Inventor-fif- Eugene CaPicho-F His fl-h-torne g.

Patented Sept 9, 1924.

\ ,508,35- T FIcE,

EUGENE R. canrcrrorr, or sorrnunoranr, NEW Year, A'SSIGNOR' 'r'o GENERALELECTRIC ooMrAuY, A CORPORATION or NEW YORK.

SYSTEM OF SELECTIVE CONTROL.

Application filed. January '1 0 all whom it may concern:

Be it known that I, EUGENE R. CARL errors, a citizen of the UnitedStates, residing at Schenectady, in the county of Sche- My inventionrelates to an improved se lective control system whereby any desiredportion of a plurality of separate paths from the supply conductor maybeselected and established at will. The invention has a particularapplication in the selective control of the direction of operation of anelectric vehicle from a point remote from the vehicle, although theinvention is not necessarily limited to such use. I

One of the-objects of the invention is to provide an arrangement wherebyafterthe particular portion of the paths for the current from a singlesupply conductor has been selected and established, the uninten- 'tionalestablishment of another portion of the paths is prevented.

My invention is particularly improvements in the system of selectivecontrol, for which John Eaton filed an application for patent, SerialNo. 526,983, filed January 4, 1922, which is assigned to the sameassignee as this invention.

In general, the system of selective control, disclosed and claimed inthe said Eaton application, comprises elect'ro-responsive switchmechanism energized from the supply conductor for establishing theparticular portion of the paths for the current from the conductor, andthe selective operation of the electro-responsive switch mechanism iscontrolled. by means of a selector relay which is controlledresponsively to the potential of the supply conductor. The potential ofthe supply conductor is controlled by means of a controller located at aremote point. While the Eaton sys% tem is entirely operative andpractical for the ordinary conditions encountered in the service forwhich the system is intended, diificulties are encountered due tounusual or certain special conditions. Thus, in case the full potentialof the supply conductor is rendered ineffective to control the selectorrelay, due for instance, to the presence of a high resistance conditionsuch as sleet or dirt on the supply conductor, dirt on the directed to4, 1922. SerialNo. 526,885.

track return when the systemis used for the control of an electricvehicle, or the trolley of the vehicle temporarily leaving the trolleywire, the selector relay may not function exactly as intended, and, may.select one portion of the paths for thecur: rent when it is desiredthat another portion be selected. Anothercondition to'bepro-a videdagainstis encountered, when the path established from the,'supplyconductor is opened, either intentionally or unintentionally. Insuch a case, it may happen that a gradually decreasing current from thesupply conductor may :cause the unintentional operation of the selectorrelay, and in case,,for example, the control system be used to governthe direction of operation of an electric vehicle, the vehicle may beunintentionally reversed at such a time. 7 My invention providesimproved means whereby this unintentional establishment of any one ofthe particular portions of the paths from the conductor is prevented.

In carrying my invention into 'efi ect in one form, I have providedelectromagnetic means-under the control ofthe potential of the supplyconductor for preventingthe operation of the selector relay after it hasoperated to select aparticular path for the current and so effectivelylock the relay in the position, to which it has been operated andthereby prevent any unintentional operation of the same.

For a better understanding of the invention, reference is had to theaccompanying drawing wherein I have illustrated an embodiment of myinvention in the selective control for an electric vehicle from a pointremote from the vehicle. Referring to the drawing, the electric vehiclehas not been shown since that would add nothing to an understanding'ofthe invention; The electric motor for driving the vehicle has anarmature 10, a comniutating'field 11 and a series field 12. Thedirection of operation of this motor and the vehicle driven thereby iscontrolled by means of the electro-respon-' sive reversing switchmechanism which comprises the double-p0le electromagnetically operatedswitch or contactor'13 for the forward direction of operation and thedouble-pole contactor 14 for the reverse direction of operation. Thesedirection contactors are suitably interlocked by means of the pivotedlocking bar 15 so that only one contactor may close at a time. Thedirection contactors 13 and 1 1 are provided for establishing separatepaths for the current from the single supply conductor 16 with which thetrolley 17 ot the vehicle is nor mally in engagement.

The selective operation of the direction contactors 13 and 1 is underthe control of the selective relay 18. This relay comprises a singleswitch member 19 Which is under the joint control of the two serieslockouttype electromagnets 20 and 21. These electromagnets are each ofthe well-known type which is magnetically held in a biased poition whenthe current in the winding of the electromagnet is above a predeterminedvalue and which causes a movable member of the electromagnet to operateto another position and be magnetically hold therein when the current inthe winding of the electromagnet is below a predetermined value. Therelays are diagrammatically illustrated as of the type fully describedin Letters Patent to Harry R. Caniield No. 1,3l4,260, dated June 22..1920, although my invention is notnecessarily limited to the particulartype of series relay disclosed in this application and covered broadlyby the said Canfield patent. The electromagnet 20 is provided with amovable magnetic member or plunger 22 which is adapted to be broughtinto engagement with the switch member 19 to tilt the same, and theelectromagnet 21 is provided with a plunger for tilting the switchmember 19 in the opposite direction. The electromagnet 20 is providedfor selecting the forward direction o'l' operation and the electromagnet21 is provided for selecting the reverse direction of vehicle operation.

The selector relay 18 is controlled by means of a reversing controllerat 2% which is also provided with means for controlling the accelerationand the speed of operation of the motor vehicle after the selected path.tor the current has been established by the operation of either one orthe other of the direction contactors 13 and. l-il. The controller 2 lis adapted to control the compaia tively high resistance resistors and26 tor controlling the selective operation ot' the relay 18. Theaccelerating and speed varying resistor 2? is adapted to be shortcircuited step by step by means of suit le contact segments on thecontroller for b= forward and reverse operation. The 1 section of thisresistor 2'? is controlled by the series eontactor 28 which is providedfor the purpose of insuring that at a portion of the resistor 27 will beincluded. in the motor armature circuit until the current taken by themotor has dropped to a predetermined value. The series lockout typec'ontactor 28 is diagrammatically illustrated as of the type fullydisclosed in Letters Patneoaeee ent to Edwin J, Murphy No. 1,352,307,dated September 7, 1920.

The unintentional operation of the selec tor relay is prevented byelectro-responsive means comprising the electromagnet 29, the winding 01which is permanently connected to the supply conductor 16 through thetrolley 17. This electromagnet is provided with a magnetic movablemember 30 which serves as a locking detent tor the pivoted switch member19. The magnetic locking member 30 is normally biased out of engagementwith the arm secured to the switch member 19, and is arranged so thatwhen the electromagnet is energized, the locking member makes engagementwith this arm 31 to prevent the operation of the switch 19 to its otherposition until after the electromagnet 29 is deenergizec. rlrlthough thegeneral controlv system is disclosed and claimed broadly in theaforesaid Eaton ap plication the particular form of selector relay whichI have selected for the purpose of illustrating my invention and theconnection of this relay in a selective system of control is disclosedand claimed in an application tor patent filed by Charles Coir nely,Serial No. 54l(5,'?76, filed lilarch 25, 1922, and assigned to the sameassignee as this invention.

As thus constructed and arranged, the op eration oi my invention is asfollows: It is believed that an understanding of the invention will bemore readily had by indicating generally a particular system in whichthe various devices are intended to operate at selected voltages orcurrent values, and l shall therefore describe my invention in thismanner, but would have it understood that my invention is notnecessarily limited to the following relation of the various parts, butthat the particular example is given for the sole purpose of obtaining aquick understanding of the invention. Let it be as sumed that thevoltage of the source of supply indicated at is volts and that theoperating electromagnets of the direction contactors 18 and 1 1 will beenergized to close at any voltage above volts, but not at any lowervoltage. Assui'ne that it is desired that the motor vehicle operate inthe forward direction. The switch member 19 of the selector relay 18 isin the proper tion for this *ClllCCiiOD oiioperation, so that by movingthe reversing controller 24 from its oil position toward the right toits first operative position the series windings or the relays 20 and 21will be connected from the source of supply through a circuit in cludingthe high resis "108 selector resistor 26, the accelerating resistance2?, supply conductor 16, trolley 17, throughthe windings of theelectromagnets 20 and 21, the armature 10 of the electric motor andcommutating .field 11 to the ground return,

which is indicated as the return conductor for the system. The value ofthe resistor 26 will be such that the potential of the supply conductor16 will be reduced to such a value that substantially 2 amperes willflow through the windings of the relays. This value of current willcause the operation of the plunger 22 of the electromagnet 20, but theplunger 23 of the electromagnet 21 will be magnetically held in itsbiased position. The operation of the plunger 22 produces no efiect onthe switch member 19, for the reason that it is already in the properposition for selecting the forward direction of operation. The voltageof the supply conductor 16 will be belew 230 volts, the value at whichthe direction contactor 13 will be energized to close, and thiscon'tactor will not be energized to close until the controller 24:

is advanced to its second operative position, at which the resistor 26will be excluded from the circuit. When this happens, the potential ofthe supply conductor 16 will be increased above 230 volts and thedirection contactor will be energized to close through the switch member19 ot' the selector relay. When the contactor 13 closes, one path forthe motor current is closed from the plus side of the source of supply32, through the accelerating resistor 27, supply conductor 16, trolley17 upper contacts of the contactor 13, through the series field 12 ofthe motor, through the series holding winding 33 associated with thelower contacts of the contactor 13, lower contacts of contactor 13,through the motor armature 10 and commutating field 11 to the groundreturn. The locking electromagnet 29 for the selector relay will besubstantially simultaneously energized to attract its locking member 30with the closing of the direction contactor 13. The winding of thelocking electromagnet 29 and the magnetic circuits of this electromagnetare designed so that the locking member 30 will not be attracted intolocking engagement with the arm' 31 until a voltage is applied to thewinding which is above the voltage at which the re lays 20 and 21 willoperate so as not to interfere with the operation of the relays undernormal conditions, but after the looking member 30 is operated to theattracted position it will be maintained in the at tracted position eventhough the current through the winding of the electromagnet drops to avery lowvalue.

In order to accelerate the electric motor, the controller 24 is advancedtoward the right through its successive operating positions until thefinal position has been reached at which the winding of the serieslock-out type contactor 28 is included in circuit. When the currenttaken by the motor has dropped to a predetermined value this seriescontactor will close and short circuit the final section of the resistor27, thereby connecting the motor directly across the source of supply.If for any reason the ei fective potential applied to the motor andapplied to maintain the direction contactor 13 closed should drop belowthe value at which the direction contactor 13 will open, the windings ofthe electromagnets of the selector relay are included in series with themotor armature, so that the current through these windings may drop tosuch a value that the plunger 23 of the electromagnet 21 will operate toendeavor to throw the switch member 19 to its opposite position. Thelocking electromagnet 29 is provided for taking care oi conditions ofthis general nature. If, for example, the trolley 17 should temporarilyleave the conductor 16 and draw an arc, the direction cont-actor 13 mayopen and in this case the relay windings are included in series with theare, so that the relay may tend to select for the other direction ofoperation in such a condition. Another condition provided against by thelocking electromagnet 29 is the drawing of an arc at the final segmentof the con.- troller 24L when the controller is returned to its of?position. The establishment of such an are at the controller for asmallinterval of time may cause the selector relay to attempt to operate andestablish the connections for the opposite direction of rotation.Another condition provided against by the provision of the lockingelectromagnet is the presence of sleet or dirt on the trolley wire 16 orsome high resistance condition on the track return for the vehicle. 3 i

It will be understood that in case it is desired to operate the motorvehicle in the reversedirection the controller 24 is first returned toits off position. The direction contactor 13 will thereupon bedeenergized and open, and the winding of the locking electromagnet- 29will be deenergized so as to release the locking member 30. In order toreverse the direction of motor operation, the controller 24 is movedfrom the 01f position toward the left to its first operative orselective position. Both of the high re sistance resistors 25 and 26 arethereupon included in the circuit of the windings of the electromagnets20 and 21 of the selector relay 18. The two resistors 25 and 26 willlimit the value of current through the relay windings to 1 ampere, torexample. With this value or current, the electromagnet 20 will not besufficiently energized to operate its plunger 22, but the electromagnet21 will be sufliciently energized to operate its plunger 23 and therebytilt the switch memof current through the winding of the lookingelectromagnet 29 will not be suiiicient to cause the lockingelectromagnet to operate. When the controller 2% is moved to its secondoperative position to the left, substantially full potential is appliedto the supply conductor 16, and the direction contactor id will beenergized to close to establish the circuit for the motor from thesupply conductor and the locking electromagne-t 29 will be energized. toatt ct the locking member 30 to prevent further unintentional opera tionof the selector relay. The path for the motor current will now beestablished from the source of suppl through the acceleratif resistor27, the supply conductor 16, trolley ll} lower contacts of the directionc :-ntactor 314i, through the series holding coil through the iirmtorfield 2.2 in a direction opposite to that established by the closing ofthe direction contactor 13, through the upper contacts oi? the directioncontactor 14, motor armature l0 and eommut-ating field ll. to the groundreturn. The acceleration of the motor will be governed by shortcircuiting step by step the accelerating resistor 27. The lockingelectromagnet 29 will now prevent the unintentional operation of theselector relay in the same manner that previously explained.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation oi? my invention, together with theapparatus which I now consider to represent the best embodiment thereof,but I desire to have it understood that the apparatus shown is onlyillustrative and that the invention may be carried out by other means.

lVhat l claim as new and desire to secure by letters Patent of theUnited States, is

The combination in a selective system of control of a supply conductor,electro responsive switch mechanism for establishing a selected portionof a plurality of separate paths from the said conductor, anelectro-responsive relay connected to the said conductor and operatedresponsively to the potential of the conductor for controlling theenergization of the said switch .mechaitiism to select the portion ofthe said paths "from the said conductor to be established, and electroresponsive means energized responsively to the potential of the saidconductor for locking the said relay from further unintentionaloperation after the desired portion of the said paths has been selected.

2. The combination in a selective system of control of a supplyconductor, electroresponsive switch mechanism for establishing aselected portion of a plurality of separate paths from the saidconductor, an electro-responsive relay connected to the said conductorand operated responsively to the 3. The combination in a selectivesystem oi control of a supply conductor, a plurality of separate pathsfrom said conductor, electroresponsive switch mechanism for establishinga selected portion of said paths, an electro-responsive relay connectedto the said conductor and operated responsively to the potential ot' theconductor for controlling the energization of the said switch mechanismto select the portion of the said paths from the said conductor to beestablished, and an electron'iagnetic lock energized from the saidconductor for preventing turther unintentional operation oi the saidrelay utter the desired portion oi? the said paths l'xas been selectedthe said lock arranged to operate at higher value of potential than. theoperating potential of said relay and maiiuiain its locking efi ect at alower value of potential than the operating potential of said relay.

Z The combination in a selective system ot' a control of a supplyconductor, electro responsive switch mechanism for establishing aselected portion of a plurality of separate paths from the saidconductor a relay connected to the said conductor for controlling theenergization of the said switch mechanism to select the desired portionof the said paths to be established, electro magnetic operating meansfor the said. relay arranged to operate within one range of values ofthe potential of said conductor and be magnetically held "from operatingat higher values of the potential of the said conductor, andelectro-responsive means for locking the said relay to preventtheunintentional operation of the same, the said locking means arranged tooperate at a higher potential of the supply conductor than the saidoperating range of said relay and to n- "intain its locking effect at apoten-- tial of the supply conductor below the said operating range ofpotential oi the said relay.

A reversing control system for electric motors comprising a motor supplyconductor electro-responsive reversing switch mechanism, a selectorrelay operated responsively to the potential of the supply conductor forcontrolling the said switch mechanism, a reversing controller forcontrolling the potential of the supply conductor to con trol theoperation of the said relay, and an.

"too

able in the other direction to connect the supply conductor to thesource of supply with the said resistor excluded, electroresponsivemotor reversing switch mechanism, an electro-responsive selector relay 7operated responsively to the inclusionand GXClUSlOD of the said reslstor1n clrcult With the said supply conductor for controlling v i the saidreversing switch mechanism, and a;

normally released electromegnetically con trolled lock energized fromthe said supply conductor for preventing the operation of the said relayexcept under the control of the said controller.

In Witness whereof, I have hereunto set my hand this 28th day ofDecember, 1921 EUGENE R. CARIGHOFF

